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General
Climate Information
General Weather
Severe Weather
Other Ways of Finding What You Need
 

Looking for Something?

 
What are the sunrise & sunset times for ....... ?
What are the moonrise & moonset times for ...... ?
When is the next full moon?
Where can I find tide tables?
Where can I find wave and swell information?
How can I get a Bureau of Meteorology calendar?
Where can I get international weather information?
Where can I find a coloured satellite photo?
Do you have a list of Australian weather station locations on the web?
How do I get climate data?
How do I get geospatial data or a web map service?
Where can I get planet data?
Where can I find forecasting terms: fine; dry; cloudy?
Can I download information in a way that I can use directly using a computer program / script?
How do I get the Previous Month's Features page?
 

 

General

 

Why is the product I want "old"?

The weather charts, satellite images, radar images, forecasts and warnings are all updated regularly and automatically. There are occasional system faults, but if you are seeing old products its most likely that you are having a problem with caching. Either your browser is holding an old version of the product you want and not fetching a new one from our site. Make sure you click on "Refresh" / "Reload" (whichever is appropriate for your browser). Holding down the shift key while clicking on "Refresh" / "Reload" does direct some browsers (certainly Netscape) to not check their local cache first but re-fetch the document over the network. Or your Internet Service Provider (ISP) is caching (keeping a copy of the web pages) on their server(s). You may have to contact your ISP.

 

 

Climate Information

 
Useful sections of the site for climate
 
Electronic Climate Products Data, Maps, Books
National Climate Centre Products Listing of products and availability
 
What are the Bureau of Meteorology's Seasonal Climate Outlooks?
 
General statements about the probability or risk of wetter or drier than average weather over a three-month period. The outlooks are based on the statistics of chance (the odds) taken from rainfall and sea surface temperature records. They are not, however, categorical predictions about future rainfall, and they are not about rainfall within individual months of the three-month outlook period.
 
How accurate are the outlooks?
 
In the places and seasons where the outlooks are most skillful, the eventual outcome (above or below median) is correctly given the higher chance about 70 to 80% of the time. In the least skill areas, the outlooks perform no better than random chance or guessing. The rainfall outlooks perform best in eastern and northern Australia between July and January, but are less useful in autumn and in the west of the continent. The skill at predicting seasonal maximum temperature peaks in early winter and drops off marginally during the second half of the year. The lowest point in skill occurs in early autumn. The skill at predicting seasonal minimum temperature peaks in late autumn and again in mid-spring. There are also two distinct periods when the skill is lowest - namely late summer and midwinter. However, it must always be remembered that the outlooks are statements of chance or risk. For example, if you were told there was a 50:50 chance of a horse winning a race but it ran second, the original assessment of a 50:50 chance could still have been correct.
 
How should the outlooks be used?
 
As another tool in risk management and decision making. The benefits accrue from long-term use, say over 10 years. At any given time, the probabilities may seem inaccurate, but taken over several years, the advantages of taking account of the risks will outweigh the disadvantages. For more information on the use of probabilities, farmers could contact their local departments of agriculture or primary industry.
 
What do forecasters mean by "wetter or drier than average", or "warmer or cooler than average"?
 

These comments mean that it has been above or below the median rainfall, average maximum temperature, or average minimum temperature for the three-month period.

The median is a useful measure of "normal" rainfall. In the long term, rainfall is above median in one half of years, and below median in the other half.
For example, from July to September at Mackay in Queensland, one-half of 3-month rainfall totals have been below 80mm, and one-half have been above. If rainfall was above 80mm in that period it would be "wetter than average" or above median. Over the long haul there is a 50% chance of this occurring. In terms of odds this is even money. Note that the average maximum temperature is the average of all the daily highest temperatures for the period. Similarly, the average minimum temperature is the average of all the daily lowest temperatures for the period

 
Will categorical outlooks ever be issued? (E.g. It WILL be drier than average.)
 
Very unlikely. There is a certain level of natural variability in the climate which is chaotic and unpredictable. This is particularly the case with rainfall. For example, rainfall in a season can be significantly above average in one region, and significantly below average less than 50km away.
 

 

General Weather

 
Useful sections of the site for weather
 
Conversion Calculators Calculators for converting any weather unit of measurement
The Weather Map Preparing, reading and using weather maps
Weather Education What is weather? History - causes - forecasting - related pages
Weather Charts About the weather charts
 
Where do I find forecasts for my area?
 
All forecasts can be found by selecting Weather & Warnings; State of interest; Forecasts. Then select your area of interest. 7-day outlooks can be found within the state forecast.
 
Is there a link between sunspot activity and the weather?
 
The Bureau of Meteorology does not currently track sunspots. Information can be found at http://www.meadows3.demon.co.uk/, or by searching the Internet for 'sunspots'.
 
How can I build my own rain gauge?
 
There is no information on our website for this topic however the following site has school activities including how to build a barometer and various other weather instruments. http://www.sasked.gov.sk.ca/docs/elemsci/g4fsld1.html
 

 

Severe Weather

 
Useful sections of the site for severe weather
 
Climate of the 20th Century Major Australian climate events of the 20th Century
 
What is the difference between a tropical cyclone, a hurricane and a typhoon?
 
What we call tropical cyclones In the southern hemisphere, are called hurricanes in the Northern Hemisphere. Typhoon, a name of Chinese origin meaning 'great wind', is applied to intense tropical cyclones which occur in the western Pacific Ocean. The terminology used in Australia is "Tropical Cyclone" and "Severe Tropical Cyclone". We don't use the terms tropical storm, severe tropical storm, hurricane or typhoon.
 
Where can I find a cyclone plotting map?
 
Plotting maps are published in telephone books and are available from local emergency services and Bureau of Meteorology offices in the tropics. It is also available on the Weather by Fax Service at: 1902 935 5473.
 
Can I name a cyclone?
 
No. Each tropical cyclone region of the world has a pre-prepared alphabetical list of tropical cyclone names, alternating between male and female. When a tropical cyclone is identified, it gets the next name on the list. If the tropical cyclone ends up being very significant in its impact, that name is never used again.
 

 

Other Useful Sections of the Site

 

To find other documents related to the specific topic you are interested in, also look under Learn about Meteorology: Alphabetic List of Topics, and use the Search facility.

Use the Glossary and Weather Words sections to find definitions of terms used on this site.

The site map can also be used to find information.